First, if you haven't seen 2001: A Space Odyssey stop now and go rent it. Yes it's old and slow, but still amazing. Ok, now you've seen the space station docking scene? Imagine using The Claw... It lets you form a docking attachment with a target wherever it happens to connect. Match velocities so your ship is centered "over" the axis of rotation of the other ship - you can view your ship from behind and see the other one turning clockwise (or anti) and your ship is directly opposite the point that it's turning around. Point your Claw towards that point and arm the Claw (and "control from here" on the Claw). F5 for safety, if you do that sort of thing. Turn off SAS or whatever mod may be stabilizing you and move in at 1 to 2 m/s while matching rotation (Q and E) with the target. Hum the Blue Danube Waltz... Boom, you dock and as an extra bonus, if you hit the center your ship's thrust is aligned through the target's center of mass, so you can maneuver. Just make sure the target has no active thrusters as your controls will throttle all the active engines at once.